Mill for grinding



' UNITED STATES PATENT oEEroE.

DAVID MARSH ELI B. NICHOLS, OF FAIRFIELD, CONNECTICUT.

MILL FOR GRINDING.

Specification of Letters Patent No. 6,834, dated October 30, 1849.

To all 'whom t may concern.'

Be it known that we, DAVID MARSH and ELI B. NICHOLS, of Fairfield,Fairfield county, State of Connecticut, millers, have invented and madeand applied to use certain new and useful improvements in theconstruction of the eye and spindle cups of grinding-mills by which thegrain is prevented from jumping out of the center, at the same timeforcing it down, thereby grinding more quickly than without theseimprovements, which include an improvement in the connection of thedriving-spindle and parts beneath, for which improvements we seekLetters Patent of the United States, and that the said improvements arefully and substantially set forth and shown in the following descriptionand in the drawing annexed to and making part of this specification,wherein- Figure 1 is a sectional elevation of the eye, showing the twostones, and parts'attached: the Fig. 2 is an elevation, and Figs. 3 and4 are plans, of the bottom and top of the barrel, which we use to eectthese objects; the other figures are separately referred to; and thesame letters and numbers, as marks of reference, apply to the like partsin all the several figures.

In these A, is t-he nether stone; B, the running stone, constructed inany manner, and of any suitable materials; the nether stone receives thestill spindle a, wit-h a cup l, inthe upper end, taking a changeablecenter pin 2, in a cast iron box b, which is constructed with a grooveand rabbet 3, on the under edge, to overlie the edges of the cup l,preventing the accumulation of dust, &c., as shown in plan, in thedetached Fig. 6 the upper end of the pin 2, forms a center to take thebail 5, which sets in notches 6, 6, in the edges 4, 4, of the cup, seethe detached Fig. 5, on the upper side of the box b,whi ch cup 4,receives the forked ends of the spindle 0, so that by 'thisconstruction, the forks going Vover the bail, and into the cup, areprevented from separating by the edges 4, of the cup.

The ends of the bail 5, are formed solid in the stone, and a cylinder,d, is fitted and secured in the eye, of the running stone B; and ironbarrel e, is fitted with a flanch, to overlie t-he curb frame, above theupper edge of the cylinder cl', and encircles the spindle to near theupper edge of the bail 5, and has formed within it a spiral worm orscrew 6,

leading from the top, and making nearly one turn inside the cylinder,the inner edges of this terminates in a fence, that sets nearly againstthe spindle c, and forms a slot 7 to the edge of the cylinder or barrel;this opening takesvthe end of the hopper slice, the fence being the sameheight as the top of the cylinder e, and increasing in depth, as thescrew piece 6, descends; this cylinder e, is made less in its externaldiameter, than the internal diameter of the cylinder cl, and has on itsoutside, between the two cylinders, two or more worm iianches 8, 8,running in the same direction as the piece 6, these outside threads donot quite touch the inside of the cylinder d. Vhen thus constructed, andpower is applied, in any convenient manner, to the shaft c, and bail 5,these are made to rotate, and carry the cup b, and bail 5, with therunning stone B, in the direction denoted by the arrow yin the plan,Fig. 3, the hopper supplying grain or other materials to be ground,through the slot 7 the grain falls between the stones, and is carriedaround, under the plate 6, which screws it down, preventing the grainfrom jumping out of the eye, and forcing it to enter between the stones,and the screw pieces 8, 8, prevent any grain from getting between thecylinders, by acting in the same manner as the plate 6.

It will be seen, that the sizes and proportions of the parts may bevaried, to suit the materials operated on; and that in this arrangement,we obviate the difiiculty practically experienced, in the mills patentedon the thirteenth of March, one thousand eight hundred and forty four,by us; viz. the splitting the fork of the spindle, as the sides of thecup effectually hold the same; and these improvements, in the shape ofthe cup, may be used either alone, or with other improvements containedin the above mentioned patent, and the feeding arrangement may be usedwith the common mill; although we prefer and use it, with the cup shownherein,A and with the other improvements previously patented, as abovereferred to.

Ve do not claim to have invented a cup, to intervene between the bailspindle and fixed centering cup, but

Vhat we do claim as new, and of our own invention, and desire to secureby Letters Patent of the U. S. is

l. The construction and application of the direction of the stationaryscrew anch, substantially as described and shown.

In witness whereof, we have hereunto set our signatures this twentiethday of Octo- 15 ber, one thousand eight hundred and forty eight.

- DAVID MARSH.

ELI BfNICHOLS. Witnesses:

JEsUr BANKS, JOHN MOODY.

